The blasts happened while an open-air performance was being staged outside the Kantajir temple during an annual fair in Dinajpur district on Saturday morning, said Ruhul Amin, the local police chief.

In recent months, Bangladesh has experienced a series of attacks on secular bloggers, foreigners and minority groups amid concerns that religious extremism is on the rise in the Muslim-majority country.

No group immediately claimed responsibility for Saturday's attack. Police have detained six men for questioning in connection with the blasts, Mr Amin said.

Six of the injured were being treated at a nearby hospital. Four others suffered less serious injuries.

Mizanur Rahman, another senior police official, said investigators were trying to determine the motive for the attack.

Previous attacks this year have been claimed by local Islamist radical groups and the Islamic State group.